870 resultados para lock and key model
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Every year, debris flows cause huge damage in mountainous areas. Due to population pressure in hazardous zones, the socio-economic impact is much higher than in the past. Therefore, the development of indicative susceptibility hazard maps is of primary importance, particularly in developing countries. However, the complexity of the phenomenon and the variability of local controlling factors limit the use of processbased models for a first assessment. A debris flow model has been developed for regional susceptibility assessments using digital elevation model (DEM) with a GIS-based approach.. The automatic identification of source areas and the estimation of debris flow spreading, based on GIS tools, provide a substantial basis for a preliminary susceptibility assessment at a regional scale. One of the main advantages of this model is its workability. In fact, everything is open to the user, from the data choice to the selection of the algorithms and their parameters. The Flow-R model was tested in three different contexts: two in Switzerland and one in Pakistan, for indicative susceptibility hazard mapping. It was shown that the quality of the DEM is the most important parameter to obtain reliable results for propagation, but also to identify the potential debris flows sources.
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General introductionThe Human Immunodeficiency/Acquired Immunodeficiency Syndrome (HIV/AIDS) epidemic, despite recent encouraging announcements by the World Health Organization (WHO) is still today one of the world's major health care challenges.The present work lies in the field of health care management, in particular, we aim to evaluate the behavioural and non-behavioural interventions against HIV/AIDS in developing countries through a deterministic simulation model, both in human and economic terms. We will focus on assessing the effectiveness of the antiretroviral therapies (ART) in heterosexual populations living in lesser developed countries where the epidemic has generalized (formerly defined by the WHO as type II countries). The model is calibrated using Botswana as a case study, however our model can be adapted to other countries with similar transmission dynamics.The first part of this thesis consists of reviewing the main mathematical concepts describing the transmission of infectious agents in general but with a focus on human immunodeficiency virus (HIV) transmission. We also review deterministic models assessing HIV interventions with a focus on models aimed at African countries. This review helps us to recognize the need for a generic model and allows us to define a typical structure of such a generic deterministic model.The second part describes the main feed-back loops underlying the dynamics of HIV transmission. These loops represent the foundation of our model. This part also provides a detailed description of the model, including the various infected and non-infected population groups, the type of sexual relationships, the infection matrices, important factors impacting HIV transmission such as condom use, other sexually transmitted diseases (STD) and male circumcision. We also included in the model a dynamic life expectancy calculator which, to our knowledge, is a unique feature allowing more realistic cost-efficiency calculations. Various intervention scenarios are evaluated using the model, each of them including ART in combination with other interventions, namely: circumcision, campaigns aimed at behavioral change (Abstain, Be faithful or use Condoms also named ABC campaigns), and treatment of other STD. A cost efficiency analysis (CEA) is performed for each scenario. The CEA consists of measuring the cost per disability-adjusted life year (DALY) averted. This part also describes the model calibration and validation, including a sensitivity analysis.The third part reports the results and discusses the model limitations. In particular, we argue that the combination of ART and ABC campaigns and ART and treatment of other STDs are the most cost-efficient interventions through 2020. The main model limitations include modeling the complexity of sexual relationships, omission of international migration and ignoring variability in infectiousness according to the AIDS stage.The fourth part reviews the major contributions of the thesis and discusses model generalizability and flexibility. Finally, we conclude that by selecting the adequate interventions mix, policy makers can significantly reduce the adult prevalence in Botswana in the coming twenty years providing the country and its donors can bear the cost involved.Part I: Context and literature reviewIn this section, after a brief introduction to the general literature we focus in section two on the key mathematical concepts describing the transmission of infectious agents in general with a focus on HIV transmission. Section three provides a description of HIV policy models, with a focus on deterministic models. This leads us in section four to envision the need for a generic deterministic HIV policy model and briefly describe the structure of such a generic model applicable to countries with generalized HIV/AIDS epidemic, also defined as pattern II countries by the WHO.
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Gut microbiota has recently been proposed as a crucial environmental factor in the development of metabolic diseases such as obesity and type 2 diabetes, mainly due to its contribution in the modulation of several processes including host energy metabolism, gut epithelial permeability, gut peptide hormone secretion, and host inflammatory state. Since the symbiotic interaction between the gut microbiota and the host is essentially reflected in specific metabolic signatures, much expectation is placed on the application of metabolomic approaches to unveil the key mechanisms linking the gut microbiota composition and activity with disease development. The present review aims to summarize the gut microbial-host co-metabolites identified so far by targeted and untargeted metabolomic studies in humans, in association with impaired glucose homeostasis and/or obesity. An alteration of the co-metabolism of bile acids, branched fatty acids, choline, vitamins (i.e., niacin), purines, and phenolic compounds has been associated so far with the obese or diabese phenotype, in respect to healthy controls. Furthermore, anti-diabetic treatments such as metformin and sulfonylurea have been observed to modulate the gut microbiota or at least their metabolic profiles, thereby potentially affecting insulin resistance through indirect mechanisms still unknown. Despite the scarcity of the metabolomic studies currently available on the microbial-host crosstalk, the data-driven results largely confirmed findings independently obtained from in vitro and animal model studies, putting forward the mechanisms underlying the implication of a dysfunctional gut microbiota in the development of metabolic disorders.
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The publishing industry is at a turning point. Facing the first major disruptive innovation in five centuries, its long-established structure and business model are at stake. Building on literature based on the pitfalls for incumbents, we interviewed key executives from the major publishers in Brazil to understand their perspective. We find that not only are they facing those pitfalls, but we also propose a new one, The Industry View Trap, concerning challenges created by convergence, the difficulty to deal with changes in the ecosystem and the fact that the very definition of the industry you're part of might have changed.
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Chez les animaux, les jeunes dépendant des parents durant leur développement sont en compétition pour obtenir la nourriture, qu'ils quémandent par des cris et postures ostentatoires et se disputent physiquement. Les frères et soeurs n'ont pas la même compétitivité, en particulier s'ils diffèrent en âge, et leur niveau de faim fluctue dans le temps. Comme dans tout type de compétition, chacun doit ajuster son investissement aux rivaux, c'est à dire aux besoins et comportements de ses frères et soeurs. Dans le contexte de la famille, selon la théorie de sélection de parentèle, les jeunes bénéficient de leur survie mutuelle et donc de la propagation de la part de gènes qu'ils ont en commun. L'hypothèse de la « négociation frères-soeurs » prédit que, sous certaines conditions, les jeunes négocient entre eux la nourriture, ce qui réduit les coûts de compétition et permet de favoriser les frères et soeurs les plus affamés. La littérature actuelle se focalise sur les signaux de quémande entre enfants et parents et les interactions compétitives frères-soeurs sont étudiées principalement au sein de paires, alors que les nichées ou portées en comprennent souvent de nombreux. Cette thèse vise à mieux comprendre comment et jusqu'à quel point plusieurs jeunes ajustent mutuellement leurs signaux de besoin. C'est une question importante, étant donné que cela influence la répartition de nourriture entre eux, donc la résolution du conflit qui les oppose et à terme leur valeur évolutive. Le modèle d'étude est la chouette effraie (Tyto alba), chez laquelle jusqu'à neufs poussins émettent des milliers de cris chacun par nuit. Ils négocieraient entre eux la prochaine proie indivisible rapportée au nid avant que les parents ne reviennent : un poussin affamé crie plus qu'un autre moins affamé, ce qui dissuade ce dernier de crier en retour et par la suite de quémander la nourriture aux parents. L'investissement optimal correspondrait donc à écarter son frère en permanence vu que l'arrivée des parents est imprévisible, mais à moindre coût. Dans un premier axe, nous avons exploré au sein de dyades les mécanismes acoustiques permettant aux poussins de doser leur effort vocal durant les heures de compétition où ils sont laissés seuls au nid. Nous avons trouvé que les poussins évitent de crier simultanément, ce qui optimiserait la discrimination du nombre et de la durée de leurs cris, lesquels reflètent de façon honnête leur niveau de faim et donc leur motivation. L'alternance des cris paraît particulièrement adaptée au fait que les poussins se fient à des variations temporelles subtiles dans le rythme et la durée de leurs vocalisations pour prendre la parole. En particulier, allonger ses cris tout en criant moins dissuade efficacement le rival de répondre, ce qui permet de monopoliser la parole dans de longs « monologues ». Ces règles seraient universelles puisqu'elles ne dépendent pas de la séniorité, de la faim, ni de la parenté et les poussins répondent à un playback de façon similaire à un vrai frère. Tous ces résultats apportent la première preuve expérimentale que les juvéniles communiquent de façon honnête sur leurs besoins, ajustent activement le rythme de leurs cris et utilisent des composantes multiples de leurs vocalisations d'une façon qui réduit le coût de la compétition. De plus, il s'agit de la première démonstration que des règles de conversation régissent de longs échanges vocaux chez les animaux de façon comparable aux règles basiques observées chez l'Homme. Dans un second axe, nous avons exploré les stratégies comportementales que les poussins adoptent pour rivaliser avec plusieurs frères et soeurs, par le biais d'expériences de playback. Nous avons trouvé que les poussins mémorisent des asymétries de compétitivité entre deux individus qui dialoguent et répondent plus agressivement au moins compétitif une fois qu'ils sont confrontés à chacun isolément. Dans la même ligne, quand ils entendent un nombre variable d'individus criant à un taux variable, les poussins investissent le plus contre des rivaux moins nombreux et moins motivés. En accord avec les prédictions des modèles théoriques, les poussins de chouette effraie escaladent donc les conflits pour lesquels leur chance de gagner contrebalance le plus l'énergie dépensée. Nous révélons ainsi que 1) les jeunes frères et soeurs 'espionnent' les interactions de leurs rivaux pour évaluer leur compétitivité relative, ce qui est sans doute moins coûteux qu'une confrontation directe avec chacun, et 2) dosent leur investissement vocal en fonction du nombre de rivaux actuellement en compétition et de leur motivation de façon concomitante. Ces résultats montrent que les interactions entre frères et soeurs au nid reposent sur des mécanismes similaires à ceux observés, mais encore de façon anecdotique, chez les adultes non apparentés qui se disputent les territoires et partenaires sexuels. Cette thèse souligne donc combien il est crucial de considérer dorénavant la famille comme un réseau de communication à part entière pour mieux comprendre comment les jeunes résolvent les conflits autour du partage des ressources parentales. Plus généralement, elle révèle l'importance de la dynamique temporelle des vocalisations dans les conflits et la communication des animaux. A la lumière de nos résultats, la chouette effraie apparaît comme un modèle clé pour de futures recherches sur la résolution des conflits et la communication acoustique. - In species with parental care, offspring contest priority access to food by begging through conspicuous postures and vocalisations and by physically jockeying. Siblings differ in their competitiveness, especially in the case of age and size hierarchies, and their hunger level fluctuates in time. As in competition in general, each individual should adjust its investment to opponents that is to say to its siblings' needs and behaviours. In the particular context of family, according to kin selection theory, siblings derive extra fitness benefits from their mutual survival and hence the spreading of the genes they share. The "sibling negotiation" predicts that, under certain conditions, young would negotiate among them priority access to food, which reduces competition costs and enables promoting the most hungry siblings. To date, the literature focuses on signals of need between parents and offspring and competitive interactions (in particular among siblings) are mostly studied within pairwise interactions, yet they commonly involve more numerous rivals. This PhD aims at better understanding how and the extent to which several young siblings compete through signalling. This is important since this influences how food is allocated among them, thus the outcome of sibling rivalry and ultimately their fitness. I use the barn owl (Tyto alba) as a model, in which the one to nine nestlings emit a simple noisy call thousands of times per night. Thereby, they would negotiate among them priority access to the indivisible food next delivered prior to parents' feeding visits. A hungry nestling emits more calls than a less hungry sibling, which deters it to call in return and ultimately beg food at parents. The optimal investment thus corresponds to constantly deterring the rival to compete, given that parents' arrival is unpredictable, but at the lowest costs. In the first axis of my thesis, we explored within dyads the acoustic mechanisms by which owlets dose vocal effort when competing during the hours they are left alone. We found that owlets avoid overlapping each other's calls. This would enhance the discrimination of both call number and duration, which honestly reflect individuals' hunger level and hence motivation to compete. Such antiphony seems best adapted to the fact that siblings actually use subtle temporal variations in the rhythm and duration of their calls to take or give their turn. Owlets alternate monologs, in which lengthening calls efficiently deters the rival to respond while reducing call number. Such rules depend neither on seniority, hunger level nor kinship since nestlings responded similarly to a live sibling and an unrelated playback individual. Taken together, these findings provide the first experimental proof that dependent young honestly communicate about their need, actively adjust the timing of their calls and use multicomponent signals in a way that reduces vocal costs. Moreover, this is the first demonstration of conversational rules underlying animal long-lasting vocal exchanges comparable to the basic turn-taking signals observed in humans. In the second axis, we focused on the behavioural strategies owlets adopt to compete with more than one sibling, using playback experiments. We found that singleton bystanders memorised competitive asymmetries between two playback individuals dialoguing and responded more aggressively to the submissive one once they later faced each of both alone. Moreover, when hearing a varying number of nestlings calling at varying rates, owlets vocally invested the most towards fewer and less motivated rivals. In line with predictions from models on conflict settlement, barn owls thus escalate contests in which their chance of winning best counterbalances the energy spent. These results reveal that young socially eavesdrop on their siblings' interactions to assess their relative competitiveness at likely lower costs than direct confrontation, and dose vocal effort relative to both their number and motivation. This shows that young siblings' interactions imply mechanisms similar to those observed, yet still anecdotally, in unrelated adults that contest mates and territories. This PhD therefore highlights how crucial it is to further consider family as a communication network to better understand how siblings resolve conflicts over the share of parental resources. More generally, it provides important insights into the role of the temporal dynamics of signalling during animal contests and communication. In the light of our findings, the barn owl emerges as a key model for future research on conflict resolution and acoustic communication in animals.
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The general objective of the study was to empirically test a reciprocal model of job satisfaction and life satisfaction while controlling for some social demographic variables. 827 employees working in 34 car dealerships in Northern Quebec (56% responses rate) were surveyed. The multiple item questionnaires were analysed using correlation analysis, chi square and ANOVAs. Results show interesting patterns emerging for the relationships between job and life satisfaction of which 49.2% of all individuals have spillover, 43.5% compensation, and 7.3% segmentation type of relationships. Results, nonetheless, are far richer and the model becomes much more refined when social demographic indicators are taken into account. Globally, social demographic variables demonstrate some effects on each satisfaction individually but also on the interrelation (nature of the relations) between life and work satisfaction.
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Many dynamic revenue management models divide the sale period into a finite number of periods T and assume, invoking a fine-enough grid of time, that each period sees at most one booking request. These Poisson-type assumptions restrict the variability of the demand in the model, but researchers and practitioners were willing to overlook this for the benefit of tractability of the models. In this paper, we criticize this model from another angle. Estimating the discrete finite-period model poses problems of indeterminacy and non-robustness: Arbitrarily fixing T leads to arbitrary control values and on the other hand estimating T from data adds an additional layer of indeterminacy. To counter this, we first propose an alternate finite-population model that avoids this problem of fixing T and allows a wider range of demand distributions, while retaining the useful marginal-value properties of the finite-period model. The finite-population model still requires jointly estimating market size and the parameters of the customer purchase model without observing no-purchases. Estimation of market-size when no-purchases are unobservable has rarely been attempted in the marketing or revenue management literature. Indeed, we point out that it is akin to the classical statistical problem of estimating the parameters of a binomial distribution with unknown population size and success probability, and hence likely to be challenging. However, when the purchase probabilities are given by a functional form such as a multinomial-logit model, we propose an estimation heuristic that exploits the specification of the functional form, the variety of the offer sets in a typical RM setting, and qualitative knowledge of arrival rates. Finally we perform simulations to show that the estimator is very promising in obtaining unbiased estimates of population size and the model parameters.
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ABSTRACTThe identification of female flesh flies was always considered a difficult task since morphological descriptions and keys for females are rare. Even in a forensic entomology framework, where females play a major role, female flesh flies are usually not identified. In order to fill this gap in Southern Brazil fauna we provide detailed descriptions and key for the female of nine species included in four genera: Microcerella halli (Engel), Oxysarcodexia paulistanensis (Mattos), Oxysarcodexia riograndensis (Lopes), Peckia (Euboettcheria) australis (Townsend), Peckia(Euboettcheria) florencioi (Prado and Fonseca), Peckia (Pattonella) intermutans (Walker), Peckia(Pattonella) resona (Lopes), Peckia (Sarcodexia) lambens (Wiedemann), and Sarcophaga(Bercaea) africa (Wiedemann). These species are distinguished mainly by genital characters as tergite 6 divided or undivided, presence of tergite 8, spermatheca morphology and vaginal plate shape.
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The wreck U Pezzo, excavated within the Saint Florent Gulf in northern Corsica was identified as the pink, Saint Etienne, a merchant ship which sank on January 31, 1769. In order to determine the composition of organic materials used to coat the hull or to waterproof different parts of the pink, a study of several samples, using molecular biomarker and carbon isotopic analysis, was initiated. The results revealed that the remarkable yellow coat, covering the outside planks of the ship's bottom under the water line, is composed of sulfur, tallow (of ox and not of cetacean origin) and black pitch which corresponds to a mixture called ``couroi'' or ``stuff'. Onboard ropes had been submitted to a tarring treatment with pitch. Hairs mixed with pitch were identified in samples collected between the two layers of the hull or under the sheathing planking. The study also provides a key model for weathering of pitch, as different degrees of degradation were found between the surface and the heart of several samples. Accordingly, molecular parameters for alteration were proposed. Furthermore novel mixed esters between terpenic and diterpenic alcohols and the free major fatty acids (C(14:0), C(16:0), C(18:0)) were detected in the yellow coat. (C) 2009 Elsevier Ltd. All rights reserved.
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Chemoreception is a biological process essential for the survival of animals, as it allows the recognition of important volatile cues for the detection of food, egg-laying substrates, mates or predators, among other purposes. Furthermore, its role in pheromone detection may contribute to evolutionary processes such as reproductive isolation and speciation. This key role in several vital biological processes makes chemoreception a particularly interesting system for studying the role of natural selection in molecular adaptation. Two major gene families are involved in the perireceptor events of the chemosensory system: the odorant-binding protein (OBP) and chemosensory protein (CSP) families. Here, we have conducted an exhaustive comparative genomic analysis of these gene families in twenty Arthropoda species. We show that the evolution of the OBP and CSP gene families is highly dynamic, with a high number of gains and losses of genes, pseudogenes and independent origins of subfamilies. Taken together, our data clearly support the birth-and-death model for the evolution of these gene families with an overall high gene-turnover rate. Moreover, we show that the genome organization of the two families is significantly more clustered than expected by chance and, more important, that this pattern appears to be actively maintained across the Drosophila phylogeny. Finally, we suggest the homologous nature of the OBP and CSP gene families, dating back their MRCA (most recent common ancestor) to 380¿420 Mya, and we propose a scenario for the origin and diversification of these families.
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This paper presents a new non parametric atlas registration framework, derived from the optical flow model and the active contour theory, applied to automatic subthalamic nucleus (STN) targeting in deep brain stimulation (DBS) surgery. In a previous work, we demonstrated that the STN position can be predicted based on the position of surrounding visible structures, namely the lateral and third ventricles. A STN targeting process can thus be obtained by registering these structures of interest between a brain atlas and the patient image. Here we aim to improve the results of the state of the art targeting methods and at the same time to reduce the computational time. Our simultaneous segmentation and registration model shows mean STN localization errors statistically similar to the most performing registration algorithms tested so far and to the targeting expert's variability. Moreover, the computational time of our registration method is much lower, which is a worthwhile improvement from a clinical point of view.
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The motivation for this research initiated from the abrupt rise and fall of minicomputers which were initially used both for industrial automation and business applications due to their significantly lower cost than their predecessors, the mainframes. Later industrial automation developed its own vertically integrated hardware and software to address the application needs of uninterrupted operations, real-time control and resilience to harsh environmental conditions. This has led to the creation of an independent industry, namely industrial automation used in PLC, DCS, SCADA and robot control systems. This industry employs today over 200'000 people in a profitable slow clockspeed context in contrast to the two mainstream computing industries of information technology (IT) focused on business applications and telecommunications focused on communications networks and hand-held devices. Already in 1990s it was foreseen that IT and communication would merge into one Information and communication industry (ICT). The fundamental question of the thesis is: Could industrial automation leverage a common technology platform with the newly formed ICT industry? Computer systems dominated by complex instruction set computers (CISC) were challenged during 1990s with higher performance reduced instruction set computers (RISC). RISC started to evolve parallel to the constant advancement of Moore's law. These developments created the high performance and low energy consumption System-on-Chip architecture (SoC). Unlike to the CISC processors RISC processor architecture is a separate industry from the RISC chip manufacturing industry. It also has several hardware independent software platforms consisting of integrated operating system, development environment, user interface and application market which enables customers to have more choices due to hardware independent real time capable software applications. An architecture disruption merged and the smartphone and tablet market were formed with new rules and new key players in the ICT industry. Today there are more RISC computer systems running Linux (or other Unix variants) than any other computer system. The astonishing rise of SoC based technologies and related software platforms in smartphones created in unit terms the largest installed base ever seen in the history of computers and is now being further extended by tablets. An underlying additional element of this transition is the increasing role of open source technologies both in software and hardware. This has driven the microprocessor based personal computer industry with few dominating closed operating system platforms into a steep decline. A significant factor in this process has been the separation of processor architecture and processor chip production and operating systems and application development platforms merger into integrated software platforms with proprietary application markets. Furthermore the pay-by-click marketing has changed the way applications development is compensated: Three essays on major trends in a slow clockspeed industry: The case of industrial automation 2014 freeware, ad based or licensed - all at a lower price and used by a wider customer base than ever before. Moreover, the concept of software maintenance contract is very remote in the app world. However, as a slow clockspeed industry, industrial automation has remained intact during the disruptions based on SoC and related software platforms in the ICT industries. Industrial automation incumbents continue to supply systems based on vertically integrated systems consisting of proprietary software and proprietary mainly microprocessor based hardware. They enjoy admirable profitability levels on a very narrow customer base due to strong technology-enabled customer lock-in and customers' high risk leverage as their production is dependent on fault-free operation of the industrial automation systems. When will this balance of power be disrupted? The thesis suggests how industrial automation could join the mainstream ICT industry and create an information, communication and automation (ICAT) industry. Lately the Internet of Things (loT) and weightless networks, a new standard leveraging frequency channels earlier occupied by TV broadcasting, have gradually started to change the rigid world of Machine to Machine (M2M) interaction. It is foreseeable that enough momentum will be created that the industrial automation market will in due course face an architecture disruption empowered by these new trends. This thesis examines the current state of industrial automation subject to the competition between the incumbents firstly through a research on cost competitiveness efforts in captive outsourcing of engineering, research and development and secondly researching process re- engineering in the case of complex system global software support. Thirdly we investigate the industry actors', namely customers, incumbents and newcomers, views on the future direction of industrial automation and conclude with our assessments of the possible routes industrial automation could advance taking into account the looming rise of the Internet of Things (loT) and weightless networks. Industrial automation is an industry dominated by a handful of global players each of them focusing on maintaining their own proprietary solutions. The rise of de facto standards like IBM PC, Unix and Linux and SoC leveraged by IBM, Compaq, Dell, HP, ARM, Apple, Google, Samsung and others have created new markets of personal computers, smartphone and tablets and will eventually also impact industrial automation through game changing commoditization and related control point and business model changes. This trend will inevitably continue, but the transition to a commoditized industrial automation will not happen in the near future.
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The objective of this work was to compare the relative efficiency of initial selection and genetic parameter estimation, using augmented blocks design (ABD), augmented blocks twice replicated design (DABD) and group of randomised block design experiments with common treatments (ERBCT), by simulations, considering fixed effect model and mixed model with regular treatment effects as random. For the simulations, eight different conditions (scenarios) were considered. From the 600 simulations in each scenario, the mean percentage selection coincidence, the Pearsons´s correlation estimates between adjusted means for the fixed effects model, and the heritability estimates for the mixed model were evaluated. DABD and ERBCT were very similar in their comparisons and slightly superior to ABD. Considering the initial stages of selection in a plant breeding program, ABD is a good alternative for selecting superior genotypes, although none of the designs had been effective to estimate heritability in all the different scenarios evaluated.
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In the administration, planning, design, and maintenance of road systems, transportation professionals often need to choose between alternatives, justify decisions, evaluate tradeoffs, determine how much to spend, set priorities, assess how well the network meets traveler needs, and communicate the basis for their actions to others. A variety of technical guidelines, tools, and methods have been developed to help with these activities. Such work aids include design criteria guidelines, design exception analysis methods, needs studies, revenue allocation schemes, regional planning guides, designation of minimum standards, sufficiency ratings, management systems, point based systems to determine eligibility for paving, functional classification, and bridge ratings. While such tools play valuable roles, they also manifest a number of deficiencies and are poorly integrated. Design guides tell what solutions MAY be used, they aren't oriented towards helping find which one SHOULD be used. Design exception methods help justify deviation from design guide requirements but omit consideration of important factors. Resource distribution is too often based on dividing up what's available rather than helping determine how much should be spent. Point systems serve well as procedural tools but are employed primarily to justify decisions that have already been made. In addition, the tools aren't very scalable: a system level method of analysis seldom works at the project level and vice versa. In conjunction with the issues cited above, the operation and financing of the road and highway system is often the subject of criticisms that raise fundamental questions: What is the best way to determine how much money should be spent on a city or a county's road network? Is the size and quality of the rural road system appropriate? Is too much or too little money spent on road work? What parts of the system should be upgraded and in what sequence? Do truckers receive a hidden subsidy from other motorists? Do transportation professions evaluate road situations from too narrow of a perspective? In considering the issues and questions the author concluded that it would be of value if one could identify and develop a new method that would overcome the shortcomings of existing methods, be scalable, be capable of being understood by the general public, and utilize a broad viewpoint. After trying out a number of concepts, it appeared that a good approach would be to view the road network as a sub-component of a much larger system that also includes vehicles, people, goods-in-transit, and all the ancillary items needed to make the system function. Highway investment decisions could then be made on the basis of how they affect the total cost of operating the total system. A concept, named the "Total Cost of Transportation" method, was then developed and tested. The concept rests on four key principles: 1) that roads are but one sub-system of a much larger 'Road Based Transportation System', 2) that the size and activity level of the overall system are determined by market forces, 3) that the sum of everything expended, consumed, given up, or permanently reserved in building the system and generating the activity that results from the market forces represents the total cost of transportation, and 4) that the economic purpose of making road improvements is to minimize that total cost. To test the practical value of the theory, a special database and spreadsheet model of Iowa's county road network was developed. This involved creating a physical model to represent the size, characteristics, activity levels, and the rates at which the activities take place, developing a companion economic cost model, then using the two in tandem to explore a variety of issues. Ultimately, the theory and model proved capable of being used in full system, partial system, single segment, project, and general design guide levels of analysis. The method appeared to be capable of remedying many of the existing work method defects and to answer society's transportation questions from a new perspective.
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The value of earmarks as an efficient means of personal identification is still subject to debate. It has been argued that the field is lacking a firm systematic and structured data basis to help practitioners to form their conclusions. Typically, there is a paucity of research guiding as to the selectivity of the features used in the comparison process between an earmark and reference earprints taken from an individual. This study proposes a system for the automatic comparison of earprints and earmarks, operating without any manual extraction of key-points or manual annotations. For each donor, a model is created using multiple reference prints, hence capturing the donor within source variability. For each comparison between a mark and a model, images are automatically aligned and a proximity score, based on a normalized 2D correlation coefficient, is calculated. Appropriate use of this score allows deriving a likelihood ratio that can be explored under known state of affairs (both in cases where it is known that the mark has been left by the donor that gave the model and conversely in cases when it is established that the mark originates from a different source). To assess the system performance, a first dataset containing 1229 donors elaborated during the FearID research project was used. Based on these data, for mark-to-print comparisons, the system performed with an equal error rate (EER) of 2.3% and about 88% of marks are found in the first 3 positions of a hitlist. When performing print-to-print transactions, results show an equal error rate of 0.5%. The system was then tested using real-case data obtained from police forces.